Bad Cats

So have I talked about my bad cats yet... I've been somewhat concerned about my cats and the puppy. The cats are sort of weird - I thought cats avoided strange dogs. But not these two. They see a dog come into the yard and if inside they go out and stalk the dog (or in one case it was a group of 5 dogs(with owners). Anyway they hunch up, put ears back and advance. I'm not sure they would actually attack - I intervene in some way. I thought the cats were getting better....but last night we had a stray dog show up at our house. Cats came out and one actually started to chase the dog. Smart dog - it ran off. Dog hung around for quite a while and I got so nervous I finally got the cats inside and locked their cat door. So anyway my fears got activated again. One cat when he gets scared can be real nasty - my vet calls him psycho-cat and won't touch him until he's knocked out. The cat is fine in the house, and both cats grew up with dogs, and never a problem there. I know not to leave pup alone with cats, but how do I introduce them and get them used to each other? Am I crazy to even try? Please help...